极小性

Under certain conditions, we prove the global convergence of the modified Broydens class of quasi-Newton methods for solving uniformly convex minimization problems.

并证明算法用于求解一致凸函数极小化问题时的全局收敛性。

Using nuclear DNA C-values for 539 angiosperms in China, we examined the variation of these values among growth forms and taxonomic groups and the relationship of these values with invasiveness. Mean DNA C-value of the 539 angiosperm species was 4.06 pg. Mean DNA C-value was(1) significantly lower for woody species (1.84 pg) than for herbaceous species(5.02 pg);(2) significantly lower for 360 dicots (2.20 pg) than for 179 monocots (7.80 pg);(3) significantly lower for annuals (2.78 pg) than for perennials(6.65 pg);(4) significantly lower for 134 weed species (1.93 pg) than for herbaceous non-weeds (6.75 pg) and for several families that have an unusually high proportion of weed species;(5) significantly lower for 47 exotic weed species (1.76 pg) than for 134 native weeds (1.93 pg), but significantly lower than that of "non-weedy" herbaceous species (6.75 pg);(6) lower for weeds than for "non-weedy" species in same genus or family; and (7) in herbaceous species, generally lower for weedy compared to "non-weedy" species, with some exceptions such as Avena fatua, whose DNA C-value is as high as 14.15 pg, contrarily, and some "non-weedy" herbaceous species in Cruciferae and Cucurbitaceae with very low values.

统计了中国境内有分布的539种被子植物的DNA C-值，分析了它们在不同分类群、生活型、倍性、生活史类型以及在杂草和非杂草类群中的分布情况，主要结果如下：(1)539种被子植物DNA C-值平均为4.06 pg，其中木本植物的DNA C-值平均为1.84 pg，低于草本植物的平均值(5.02 pg)；(2)双子叶植物(360种)的DNA C-值平均为2.20 pg，极明显地小于单子叶植物(179种)的平均值(7.80 pg)；(3)1年生植物的DNA C-值平均为2.78 pg，明显小于多年植物的平均DNA C-值(6.65 pg)；(4)134种杂草的DNA C-值平均为1.93 pg，明显小于非杂草草本植物的平均值(6.75 pg)，含杂草较多的科，平均DNA C-值相对较小；(5)统计的47种入侵杂草的DNA C-值平均为1.76 pg，略小于134种杂草的平均DNA C-值(1.93 pg)，极显著地小于非杂草性草本植物(6.75 pg)；(6)以科为单位，不同科的DNA C-值存在着极大的差异；(7)DNA C-值与染色体倍性的关系并不明显，但是，随着倍性的增加，基因组变小；(8)在同一科、属中，与非杂草相比，典型杂草的DNA C-值往往偏小；(9)总体上杂草或杂草性强的植物，它们的DNA C-值比非杂草性植物的要小。

Two virus samples were collected from Malvastrum coromandelianum and these samples were tested by PCR. The results showed that a specific band about 500 bp was amplified from the samples Fz1 and Fs1 with degenerate primers PA and PB.

PCR产物测序进行序列比较发现：2组赛葵样本上病毒之间的差异极小，核苷酸序列同源性大约为96％，因此推测：这两组赛葵样本可能是由(来源：Af3BC7bab论文网www.abclunwen.com)同一种病毒侵染。

The increased amount of non--exchangeable NH4^＋-N during the incubation indicated as the following tendency, namely, Eum-Orthic Anthrosols 〉 Los - Orthic Entisols 〉 Hap-Ustic Isohumisols 〉 Ust-Sandiic Entisols. Organic material influenced significantly the increased amount of non-exchangeable NH4^＋-N （P was 0.0002, 0.0004 and 0.0003 when incubated at 20 d, 50 d and 60 d, respectively）. NH4^＋-N increased remarkably when Stlpa bungeana and Medicago sativa were added compared with no addition. The contents of non-exchangeable NH4^＋-N increased significantly when added （NH4）2SO4 compared without addition at 20 d, 40 d and 60d of incubation and P was 0.0037, 0.0033 and 0.0027, respectively. It was the result that the NH4^＋-N from （NH4）2 SO4 was fixed within the soil. The increased amount of non-exchangeable NH4^＋-N increased significantly for different soils, on which different vegetation types grew before the collection of soil samples, when incubated at 20 d （P=0.0434）, but not significantly at 40 d and 60d （P=0.7378 and 0.5375）. The increased amount of non-exchangeable NH4^＋-N in the soil, on which crop straw and nitrogen fertilizer had been incorporated for a long-term period, was larger than that of no addition, but it was not significantly different among these two fertilization models. Soil clay, total N and organic matter were positively correlated remarkably with the contents of non-exchangeable NH4^＋-N, the increased amount of non-exchangeable NH4^＋-N had no correlation with soil clay, whereas it had significantly positive correlation with total N and organic matter.

培养期间非交换性NH4^＋-N的增加量均表现为以土垫旱耕人为土最大，其次是黄土正常新成土，简育干润均腐土和干湿砂质新成土较小；添加有机物料极显著影响培养期间的非交换性NH4^＋-N增加量（培养20d、40d和60d时P分别为0.0002，0.004和0.0003），表现为紫花苜蓿和长芒草土壤非交换性NH4^＋-N的增加量均极显著高于不添加有机物料的对照土壤；在培养20d、40d和60d时，加（NH4）2SO4土样非交换性NH4^＋-N的增加量显著大于不加（NH4）2SO4土样（户分别为0.0037，0.0033和0.0027），这是土壤对（NH4）2SO4中NH4^＋-N固定的必然结果；不同植被类型土壤培养20d时的非交换性NH4^＋-N增加量差异显著（P=0.0434），培养40d和60d时差异不显著（p分别为0.7378和0.5375）；长期秸秆和氮肥配施土壤非交换性NH4^＋-N增加量大于不施肥对照土壤，但差异不显著土壤黏粒、全氮和有机质与培养0d、20d、40d和60d时土壤的非交换性NH4^＋-N含量均呈极显著正相关；而非交换性NH4^＋-N的增加量与粘粒无相关性，但与全氛和有机质呈显著正相关。

Some solvability conditions, including sublinear ,subquadralic and superquadratic, and the corresponding existence results are summed up for periodic solutions of the second order Hamiltonian systems obtained by using the minimax methods.

本文综述了用极小极大方法得到的关于二阶Hamilton系统周期解的可解性条件及相关结果，包括次线性条件，次二次条件和超二次条件等方面的近期结果。

This paper presents a nonlinear robust adaptive excitation control design procedure for multi machine power systems using back-stepping method. The control objective is to drive machine power angle and frequency to the steady-state operation point, and guarantee that the close-loop system is adaptive to the uncertainties of generator damping coefficient and d-axis reactance, and robust to model errors or bounded disturbances.

利用反步法设计了多机电力系统中的非线性鲁棒自适应励磁控制方案，控制目标是调节发电机功角和频率至稳态运行点的极小领域，并使闭环系统对发电机阻尼系数和电抗参数的不确定性具有自适应能力，且对模型误差和外部有界干扰具备鲁棒性，同时保证各控制器是分散化和本地化的。

Prove it's admissibility and give Hemmerle and Brantle's method of choosing the ridge parameters.

证明其容许性并利用Hemmerle和Brantle用于确定广义岭估计参数的方法给出极小化均方误差的无偏估计法选取岭参数。

At experimental equilibrium volume, the total energy of CaTiO〓 increased with the displacement of Ti along [001] direction and the lowest energy point is always at zero displacement of Ti. However, with a 10% volume expansion, the displacement of Ti along [001] direction results in a shallow, but well-defined double energy well and ferroelectricity appears.

钛酸钙在实验晶胞体积下，钛离子沿[001]方向的位移不会引起总能量的降低，当体积膨胀10％时，钛离子的位移会引起系统的总能量的降低，在一定的位移时总能量呈现极小值，即出现铁电性。

In Chapter 2, an existence theorem is obtained for periodic solutions of non-autonomous second order systems with even-typed potentials. We also investigate solutions of linear bounded positive self-conjugation operators equations in Hilbert Space by variation methods.

第二章主要利用临界点理论中的归药方法、极小作用原理研究具偶型位势的二阶非自治系统周期边值问题，得到了周期解的存在；利用变分方法证明了Hilbert空间中有界线性正自共轭算子方程解的存在性。

The processing time of a batch Bi in this paper is rel...

对于极小化最大完工时间问题，给出了一个复杂性为O(n2)的动态规划算法，并证明了这个算法的最优性。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐